Both ANC Rental Corp. and Dollar Thrifty Automotive Group have issued warnings to investors that third-quarter earnings will fall short of estimates as a result of the travel slowdown stemming from the Sept. 11 terrorist attacks.

"Prior to the Sept. 11 disaster, the company anticipated quarterly results to be in line with Wall Street estimates," a statement from Dollar Thrifty said. "Dollar Thrifty Automotive Group now believes its third-quarter earnings per share will be below that level. Following the attacks, airlines temporarily suspended operations, creating several days of strong car rental demand as stranded travelers rented cars to get home. As airlines reduced capacity and consumers postponed travel plans, car rental transaction levels have declined, resulting in reduced operating income."

ANC Rental Corp., which was reviewing liquidity options and a possible sale of the company prior to the terrorist attacks, is especially hard hit by the travel slowdown.

"In order to operate more efficiently, given the industry's new dynamics, ANC Rental is reviewing alternatives to reduce its fleet by 25 to 35%, preparing a revised strategic and operations plan, and examining other aggressive cost-reduction initiatives," a company statement said.

Approximately 90% of ANC's car rental transactions are linked to deplaning airline passengers, the company said. ANC is the parent company of Alamo and National.